Rapid screening of proteolytic enzymes and their inhibitors using fluorescence methods

New fluorescence methods for the determination of proteolytic enzymes and their inhibitors have been investigated. Fluorescence polarisation and energy transfer methods have both been examined and of these two approaches energy transfer methods have proven superior. Out of the energy transfer methods, the use of an over-labelled substrate, which is virtually non-fluorescent but becomes highly fluorescent upon proteolytic liberation of dye-labelled peptides, has been demonstrated to be most successful. A substrate utilising α-casein labelled with a long-wavelength BODIPY® dye has been synthesised and shown to be a suitable intramolecularly quenched conjugate for the determination of proteolytic enzymes and their inhibitors in flow-based screening programmes. [Continues.

Peer to peer multidimensional overlays: Approximating complex structures

Peer to peer overlay networks have proven to be a good support for storing and retrieving data in a fully decentralized way. A sound approach is to structure them in such a way that they reflect the structure of the application. Peers represent objects of the application so that neighbours in the peer to peer network are objects having similar characteristics from the application's point of view. Such structured peer to peer overlay networks provide a natural support for range queries. While some complex structures such as a Voronoï tessellation, where each peer is associated to a cell in the space, are clearly relevant to structure the objects, the associated cost to compute and maintain these structures is usually extremely high for dimensions larger than 2. We argue that an approximation of a complex structure is enough to provide a native support of range queries. This stems fromthe fact that neighbours are importantwhile the exact space partitioning associated to a given peer is not as crucial. In this paper we present the design, analysis and evaluation of RayNet, a loosely structured Voronoï-based overlay network. RayNet organizes peers in an approximation of a Voronoï tessellation in a fully decentralized way. It relies on a Monte-Carlo algorithm to estimate the size of a cell and on an epidemic protocol to discover neighbours. In order to ensure efficient (polylogarithmic) routing, RayNet is inspired from the Kleinberg's small world model where each peer gets connected to close neighbours (its approximate Voronoï neighbours in Raynet) and shortcuts, long range neighbours, implemented using an existing Kleinberg-like peer sampling

Utilisation d'un bio-indicateur pour le suivi des rejets radioactifs aqueux de la centrale nucléaire Gentilly-2

Pour évaluer l'impact environnemental de rejets industriels, des bio-indicateurs sont fréquemment utilisés. Dans le cas des rejets radioactifs aqueux d'une centrale nucléaire, les moules pourraient être de bons bio-indicateurs en raison des grands volumes d'eau qu'elles filtrent. Dans le cadre de ce projet, l'espèce de moules Elliptio complanata a été choisie pour étudier les rejets radioactifs aqueux de la centrale nucléaire Gentilly-2. Puisque cette centrale est de type CANDU et qu'elle rejette principalement du tritium et du carbone-14 dans l'environnement, ce sont ces deux radionucléides qui ont fait l'objet du suivi dans les moules. Pour cette étude, des centaines de moules ont été placées dans le panache des rejets aqueux de la centrale. Deux systèmes ont été utilisés : des cages positionnées à faibles distances de la source du rejet et un aquarium installé au début du rejet. Les concentrations de tritium et de carbone-14 ont été mesurées dans les moules après leur exposition, grâce à différents traitements physiques et chimiques préalables aux dosages. Les résultats des analyses montrent que les moules ayant séjourné dans les eaux de rejet de la centrale sont peu affectées par le tritium et par le carbone-14

Female rats with severe left ventricle volume overload exhibit more cardiac hypertrophy but fewer myocardial transcriptional changes than males

Aortic valve regurgitation (AR) imposes a volume overload (VO) to the left ventricle (LV). Male rats with a pathological heart overload usually progress more quickly towards heart failure than females. We examined whether a sexual dimorphism exists in the myocardial transcriptional adaptations to AR. Adult Wistar male and female rats either underwent a sham operation or were induced with AR and then followed for 26 weeks. Female AR rats gained relatively more LV mass than males (75 vs. 42%). They had a similar increase in LV chamber dimensions compared to males but more wall thickening. On the other hand, fatty acid oxidation (FAO)-related LV enzyme activity was only decreased in AR males. The expression of genes encoding FAO-related enzymes was only reduced in AR males and not in females. A similar situation was observed for the expression of genes involved in mitochondrial biogenesis or function as well as for genes encoding for transcription factors implicated in the control of bioenergetics and mitochondrial function (Errα, Errγ or Pgc1α). Although females develop more LV hypertrophy from severe VO, their myocardial gene expression remains closer to normal. This could provide survival benefits for females with severe VO

Les barrières autistiques en art-thérapie : étude de cas explorant l'expression des mécanismes relationnels et défensifs autistiques en art thérapie

This research is the observation of autistic barriers presented in art-therapy with two patients who suffer from diverse somatization problems. This is a case study, in which psychoanalytical epistemology is theoretically supported by several modern theories of the primitive development of self and object relations, notably 'autistic barriers' by Frances Tustin (1990) and 'autistic-contiguous position' by Thomas Ogden (1989). In this research, it is proposed that fibromyalgia and self mutilation, in the cases studied, are primitive autistic defense mechanisms, like the ones described by Tustin. Ogden's theory, on the other hand, permits one to theoretically position the persistence of these autistic defense phenomena in people suffering from diverse somatization problems. Ogden introduces, within the post-kleinian theory, a first position, one of object relations, named "the autistic-contiguous" position as well as a conceptual dialectic of the functioning psyche. The autistic-contiguous position is conceived as the primitive and sensory background of the paranoid-schizoid position. This research will also attempt to describe and distinguish autistic-contiguous (Ogden) and paranoid-schizoid (Klein) positions. Two clinical cases will be presented, offering signs of the presence of autistic defensive mechanisms throughout the study. The conclusions of this study will permit art-therapy to be seen as a therapy of choice, capable of transforming asymbolic experiences to symbolic ones

Quality check of cardiac MRI exams for Fallot patients: Interest of a simple formula to detect invalid exams

PurposeCardiac MRI (CMR) is the key exam for Fallot patients but remains tricky. The CMR report should at least mention left and right ventricle end-diastole volumes (Vl and Vr), ejection fraction (EFl and EFr) and pulmonary regurgitation (PR). Obviously, these variables are linked together by basic physiology rules and indeed Vl×EFl=Vr×EFr×(1-PR). We investigated the interest of using such formula as quality check during Fallot CMR exams in our center.Methods98 consecutive CMR examinations for Fallot (or Fallot-like) cardiopathy between 2010 and 2014 were retrospectively included. The exams failing to pass the formula (with a 10% tolerance) constituted the Invalid-group and a control group of the same size was also constituted. CMR of both groups were randomly submitted to a blinded senior observer. The inter-observer limits of agreements were compared for the different variables within both groups.Results(Fig. 1) 12 CMR (12%) failed to pass the validation formula. From the 24 reanalyzed CMR, only 4 failed to pass the formula (all from the Invalid-group). Two had persistent defect (VSD or ASD) which were not mentioned to the radiologist and not detected during the CMR. Two had significant artefacts in the aorta or pulmonary trunk due to sterna wires. The inter-observer disagreements for the 8 other CMR of the Invalid-group concerned the Right ventricle end-diastole volume (P<0.05).ConclusionThe use of a simple formula as quality check of CMR examinations for Fallot patients was useful to detect a total of 12% of CMR with issues. 8% of the CMR corresponded to uncertain right ventricle contours, 2% to persistent septal defects that should have been noticed during the examination and 2% to unreliable aortic or pulmonary flow due to artifacts. The formula could have permitted either to detect the anomalies or at least to conclude that the quality of the exams was impaired

Développement de marqueurs microsatellites chez les agrumes

National audienc

Normative scores for the NIH Toolbox dynamic visual acuity test from 3 to 85 years

As part of the National Institutes of HealthToolbox initiative, a computerized test of dynamic visual acuity (cDVA) was developed and validated as an easy-to-administer, cost- and timeefficient test of vestibular and visual function. To establish normative reference values, 3,992 individuals, aged 3–85 years, without vestibular pathology underwent cDVA testing at multiple clinical research testing facilities across the United States. Test scores were stratified by sociodemographic characteristics. cDVA was worse in males (p \u3c0.001) and those subjects 50 years or older, while there was no difference in dynamic visual acuity across age groups binned from 3 to 49 years. Furthermore, we used these normative cDVA data as a criterion reference to compare both the long (validated) and short versions of the test. Both versions can distinguish between those with and without vestibular pathology (p D0.0002 long; p D0.0025 short). The intraclass correlation coefficient between longand short-cDVA tests was 0.86